1. Field of the Invention
The present invention relates to a signal connecting apparatus for a folder type mobile terminal, and more particularly, to a signal connecting apparatus capable of enhancing reliability for exchanging signals between a first portion rotatably connected with a second portion and having increased strength against an external impact or torsional force.
2. Description of the Related Art
A folder type mobile terminal has a folder portion rotatably mounted about a hinged portion with a body.
According to the conventional art, a main board inside the body is connected to an inner circuit board of the folder portion using a flexible printed circuit board to transmit a signal between the body and the folder portion.
The conventional folder type mobile terminal will be explained in more detail as follows with reference to the attached drawings.
FIG. 1 is a frontal view illustrating an opened state of a folder type mobile terminal in accordance with the conventional art. FIG. 2 is a schematic view showing an inner structure of the folder type mobile terminal in accordance with FIG. 1.
A conventional folder type mobile terminal includes a body 1 and a folder portion 2 rotatably coupled to the body 1 centered about a hinged portion 3.
The body 1 is provided with a keypad 4 for inputting information. The folder portion 2 is provided with a display portion 5 for displaying characters and/or images.
The display portion 5 of the folder portion 2 is connected to a printed circuit board 6. The printed circuit board 6 disposed in the body 1 connects through a flexible printed circuit board (FPCB) 7 to the display portion 5. The FPCB 7 installation includes passing through the hinged portion 3, and bends when the folder portion 2, centered about the hinged portion 3, is rotated.
The FPCB 7 includes, in this example, a copper wire having more than 4 layers and approximately 20 data lines. In yet another example, the display portion 5 may create 65,000 colors and form 8 to 16 data lines, or alternatively more than 2 data lines may be formed for increasing brightness of an image or providing additional signal driver capability.
When the FPCB is used as a signal transmission medium between the body and the folder portion, long data lines are created along the FPCB. The long data lines create, upon data transmission, a time difference due to capacitances within of the data lines. An operation is performed to prevent generating the time difference. The operation is not easy to perform reliably. The operation results in time delays and increased costs for a mobile terminal.
Upon the folder portion or the body being rotated, the FPCB generates torsional forces during flexing which may damage the FPCB resulting in severing a data line. The severed data line in the FPCB will result in the display portion 5 becoming white or not outputting an image.
A repair of the severed data line is extremely difficult resulting in a FPCB requiring replacement. The replacement cost for an FPCB may be high. However if the FPCB is not replaced, the terminal may have degraded efficiency.
Therefore, there is a need for a system that overcomes the above problems and provides advantages over other signal connecting apparatuses.